From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Wang Subject: [PATCH 2/2] virtio-net: fix buggy features advertised by host Date: Thu, 13 Nov 2014 13:24:47 +0800 Message-ID: <1415856287-12849-2-git-send-email-jasowang@redhat.com> References: <1415856287-12849-1-git-send-email-jasowang@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1415856287-12849-1-git-send-email-jasowang@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: rusty@rustcorp.com.au, mst@redhat.com, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org Cc: netdev@vger.kernel.org List-Id: virtualization@lists.linuxfoundation.org This patch tries to detect the possible buggy features advertised by host and fix them. One example is current booting virtio-net with only ctrl_vq disabled, qemu may still advertise many features which depends it. This will trigger several BUG()s in virtnet_send_command(). This patch utilizes the fix_features() method, and disable all features that depends on ctrl_vq if it was not advertised. This fixes the crash when booting with ctrl_vq=off. Cc: Rusty Russell Cc: Michael S. Tsirkin Signed-off-by: Jason Wang --- drivers/net/virtio_net.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index ec2a8b4..d6bb5fa 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1948,6 +1948,40 @@ static int virtnet_restore(struct virtio_device *vdev) } #endif +static void virtnet_fix_features(struct virtio_device *dev) +{ + if (!virtio_has_feature(dev, VIRTIO_NET_F_CTRL_VQ)) { + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_RX)) { + pr_warning("Disable VIRTIO_NET_F_CTRL_RX since host " + "does not advertise VIRTIO_NET_F_CTRL_VQ"); + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_RX); + } + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_VLAN)) { + pr_warning("Disable VIRTIO_NET_F_CTRL_VLAN since host " + "does not advertise VIRTIO_NET_F_CTRL_VQ"); + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_VLAN); + } + if (virtio_has_feature(dev, VIRTIO_NET_F_GUEST_ANNOUNCE)) { + pr_warning("Disable VIRTIO_NET_F_GUEST_ANNOUCE since " + "host does not advertise " + "VIRTIO_NET_F_CTRL_VQ"); + virtio_disable_feature(dev, + VIRTIO_NET_F_GUEST_ANNOUNCE); + } + if (virtio_has_feature(dev, VIRTIO_NET_F_MQ)) { + pr_warning("Disable VIRTIO_NET_F_MQ since host " + "does not advertise VIRTIO_NET_F_CTRL_VQ"); + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_VLAN); + } + if (virtio_has_feature(dev, VIRTIO_NET_F_CTRL_MAC_ADDR)) { + pr_warning("Disable VIRTIO_NET_F_CTRL_MAC_ADDR since " + "host does not advertise " + "VIRTIO_NET_F_CTRL_VQ"); + virtio_disable_feature(dev, VIRTIO_NET_F_CTRL_VLAN); + } + } +} + static struct virtio_device_id id_table[] = { { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID }, { 0 }, @@ -1975,6 +2009,7 @@ static struct virtio_driver virtio_net_driver = { .probe = virtnet_probe, .remove = virtnet_remove, .config_changed = virtnet_config_changed, + .fix_features = virtnet_fix_features, #ifdef CONFIG_PM_SLEEP .freeze = virtnet_freeze, .restore = virtnet_restore, -- 1.9.1